Question

Determine a resistência equivalente:

Answer 1

$R_1 = 30\Omega\\R_2 = 80\Omega\\R_3=150\Omega$

As resistências estão em paralelo, portanto:

$\dfrac{1}{R_{eq}} = \dfrac{1}{R_1} + \dfrac{1}{R_2}+\dfrac{1}{R_3}\\\\\dfrac{1}{R_{eq}} = \dfrac{1}{30} + \dfrac{1}{80} + \dfrac{1}{150}\\\dfrac{1}{R_{eq}} = \dfrac{40+15+8}{1200}\\\dfrac{1}{R_{eq}} = \dfrac{63}{1200}\\R_{eq} = \dfrac{1200}{63}\\\boxed{\boxed{R_{eq} \approx 19,05\Omega}}$